Final answer:
To increase the tachycardia zone, one can increase the intensity and frequency of activities or stressors that raise the heart rate. Additionally, medical interventions can also alter the target HR for tachycardia. Sympathetic stimulation is required for substantial increases in HR beyond 100 bpm.
Step-by-step explanation:
The question is asking for the ways in which the tachycardia zone can be increased. There are two primary methods to achieve this:
- Increase the intensity of factors that contribute to raising the heart rate (HR), such as physical activity or emotional stress.
- Increase the frequency of these activities or stressors.
Additionally, altering the target HR for tachycardia in medical settings via medications or procedures can affect the tachycardia zone. In normal physiological conditions, any increase in HR beyond 100 bpm requires sympathetic stimulation. Factors like fever, anemia, hyperthyroidism, and hypoxia can also lead to an elevated HR. Moreover, changes in body temperature can influence the tachycardia zone, with hyperthermia increasing HR and hypothermia slowing it down. Modern pacemakers can detect body motion and breathing to adjust the HR appropriately during exercise.
It's important to note that tachycardia is typically considered abnormal in a resting patient and should be analyzed within the context of the individual's circumstances.